I have some speed problems with hyperwrt 2.0

Hello, ever since beta4 of hyperwrt v2.0 i have been having some speed problems with the wireless link of my wrtg54g v2.0 (eu version). The link speed gradually drops down to 1mbit, and then sometimes the connection is lost. Only way to fix is to reconnect to the router (although the router switch keeps operating normally) I switched back to the official firmware of linksys and the problem seems to be gone.

I noticed i am the only one with this problem, could it be the drivers for the pcmcia card ?